1. Field of the Invention
The invention relates to positioning and/or holding a plurality of fine sections of one or more electric lines along a drive way of a vehicle. The vehicle can be, for example, a track-bound vehicle such as a railway vehicle. In the case of a railway vehicle, rails are provided on which the vehicle travels.
2. Description of Prior Art
Track-bound vehicles, in particular, such as conventional railway vehicles, monorail vehicles, trolleybuses and vehicles which are guided by other means along a track, for example, mechanical means other than rails, magnetic means, electronic means and/or optical means, require electrical energy for drive along the track and to power auxiliary equipment which does not produce drive of the vehicle. Such auxiliary equipment includes, for example, lighting systems, heating and/or air-conditioning systems, ventilation and passenger information systems. In general, the invention concerns the transfer of electrical energy to the vehicle, wherein the vehicle is not necessarily (but is preferably) a track-bound vehicle. Generally speaking, the vehicle may be, for example, a vehicle having an electrically operated drive motor. The vehicle may also be a vehicle having a hybrid drive system, e.g. a system which can be operated by electric energy or by other energy, such as electrochemically stored energy or fuel (e.g. natural gas, diesel fuel or petrol).
Track-bound vehicles, in particular vehicles for public passenger transport, usually comprise a contact element for mechanically and electrically contacting a conductor along the track, such as an electric rail or an overhead line. At least one drive motor on board the vehicle is fed with the electrical power from the external track or line end produces mechanical drive energy.
Trams and other local or regional trains are operated within cities, usually via overhead lines. However, especially in historic parts of cities, overhead lines are undesirable. On the other hand, conductor rails in the ground or near the ground cause safety problems.
WO 95130556 A2 describes a system wherein electric vehicles are supplied with energy from the roadway. The all-electric vehicle has one or more on-board energy storage elements or devices that can be rapidly charged or supplied with energy obtained from an electrical current, for example a network of electromechanical batteries. The energy storage elements may be charged while the vehicle is in operation. The charging occurs through a network of power coupling elements, e.g. coils, embedded in the track. Induction coils are located at passenger stops in order to increase passenger safety.
Arranging the coils at selected locations along the length of the path of travel has the disadvantage that the energy stores on board the vehicle need a large storage capacity. In addition, if the vehicle does not reach the next coil in time, the energy needed for drive or other purposes might run out. Therefore, at least for some applications, it is preferable to transfer energy to the vehicle continuously along the path of travel, i.e. along the track.
Inductively transferring energy from the track to the vehicle. i.e. producing electromagnetic fields, particularly alternating fields, is subject to restrictions regarding EMC (electromagnetic compatibility). Firstly, electromagnetic fields can interfere with other technical equipment. Secondly, people and animals should not be permanently exposed to electromagnetic fields. At least, the respective limit values for field intensity must be observed.